According to the source, ST Telemedia is in talks to buy 74 per cent stake in the entity managing the data centre business for about $650 million and the negotiations are at an advanced stage.

Tata Communications plans to use the proceeds from the deal to reduce its debt. The company's core business debt at the end of December 2015 stood at around $1.4 billion.

When contacted, Tata Communications said that as per company's policy, it does not comment on market rumours.

"We had earlier also confirmed vide our press release dated 23 July 2015 that the company has been exploring various strategic options for its data centre infrastructure business in India and potentially Singapore," the company said.

Jio’s Rs 2,399 annual plan offers 2GB per day data that costs effectively Rs 200 per month. It also offers unlimited voice and SMS. Airtel and Vodafone Idea’s Rs 2398 and Rs 2399 annual plans, on the other hand, offer 1.5GB per day data along with unlimited voice and SMS